Angular like formatters

[fincha]

Description

I thinking of some problems I faces in my development, so I thought maybe some one else is interested in a feature like a angular one

ex:

{{ item | 'currency' }}

so you can format your output the way you wish, also supporting custom functions.

I plan to implement this for the version 3

[web-padawan]

This existed as of 0.5 in the form of polymer-filters and was deprecated due to performance reason. Of course you can do something like this now as a mixin, see also polymer-expressions for some inspiration.

BTW @justinfagnani, what is a status of polymer-expressions now when your focus is lit-html?

[TimvdLippe]

We have had similar requests, for example see #4038 (comment) You can override _parseBindings to implement this functionality. In the future, solutions like lit-html can streamline this even more, by taking advantage of the direct JS context when evaluating templates.